"to prevent overflow of the buffer, it sometimes becomes necessary to tell the computer to pause the datastream. This is accomplished through ""hardware flow control"" using extra lines on the modem–computer connection. The computer is then set to supply the modem at some higher rate, such as 320 kbit/s, and the modem will tell the computer when to start or stop sending data. As telephone-based 56k modems began losing popularity, some Internet service providers such as Netzero/Juno, Netscape, and others started using pre-compression to increase the throughput and maintain their customer base. The server-side compression operates much more efficiently than"
"one outlet to the next; each outlet is wired individually back to the hub or router next to the modem. If only one computer is required,it can be directly plugged into the modem. An alternative to a wired LAN especially useful for mobile devices is a wireless LAN, which can reduce or eliminate all the fixed wiring. Cabling for free to air TV requires the following: Antenna types vary depending on location; an urban area with nearby transmitters will require a smaller antenna than a rural site with distant stations. The antenna is often mounted outdoors on the roof or"
"slides into a PCMCIA/PC card/ExpressCard slot on a computer. USB wireless modems use a USB port on the laptop instead of a PC card or ExpressCard slot. A USB modem used for mobile broadband Internet is also sometimes referred to as a dongle. A cellular router may have an external datacard (""AirCard"") that slides into it. Most cellular routers do allow such datacards or USB modems. Cellular routers may not be modems by definition, but they contain modems or allow modems to be slid into them. The difference between a cellular router and a wireless modem is that a cellular"
"world. DC-BUS powerline modem provide communication over noisy power lines at speeds up to 1.3Mbit/s using ordinary UART, LIN, SPI and CAN protocols. The WiFi and WiMax standards use wireless mobile broadband modems operating at microwave frequencies. Modems which use a mobile telephone system (GPRS, UMTS, HSPA, EVDO, WiMax, etc.), are known as mobile broadband modems (sometimes also called wireless modems). Wireless modems can be embedded inside a laptop or appliance, or be external to it. External wireless modems are connect cards, USB modems for mobile broadband and cellular routers. A connect card is a PC Card or ExpressCard which"
"In fact, broadband modems fit the definition of ""modem"" because they use complex waveforms to carry digital data. They use more advanced technology than dial-up modems: typically they can modulate and demodulate hundreds of channels simultaneously or use much wider channels than dial-up modems. Direct broadcast satellite, WiFi, and mobile phones all use modems to communicate, as do most other wireless services today. Modern telecommunications and data networks also make extensive use of radio modems where long distance data links are required. Such systems are an important part of the PSTN, and are also in common use for high-speed computer"
"the DCD signal to be configured. Typical options available include ""always assert DCD"", ""assert DCD only when connected"", and ""always assert DCD except immediately after sensing a disconnect"". The meaning of DCD differs when the modem is in fax or voice modes. In these modes, its importance is diminished. A frequent use of a serial port is for a direct computer-to-computer connection. This requires an adapter called a null modem, which isn't actually a modem in the traditional sense, but rather a connector plug that simply crosses the complementary pins on two serial ports so the two sides can communicate."
"is also used to identify internet USB keys. Vodafone brands this type of device as a Vodem. Often a mobile network operator will supply a 'locked' modem or other wireless device that can only be used on their network. It is possible to use online unlocking services that will remove the 'lock' so the device accepts SIM cards from any network. Standalone mobile broadband modems are designed to be connected directly to one computer. In the past the PCMCIA and ExpressCard standards were used to connect to the computer. As USB connectivity became almost universal, these various standards were largely"
"mode they are a modem. Typically they only ship with Windows device drivers, sometimes Mac device drivers as well. In any case, they seemingly seldom, if ever, ship with Linux device drivers. What normally happens with Windows is the device starts up as a USB flash drive, the hardware drivers are installed and then they are responsible for ""switching"" the device in to modem mode so you can use it. This ""switch"" is done via some codes, specific to the device, which controlling software can pass as a command to switch from disk to modem mode. The virtual CD-ROM switching"
"detection and configuration. Multiple devices have been described as ""residential gateways"": or certain combinations of the above. A modem (e.g. DSL modem, Cable modem) by itself provides none of the functions of a router. It merely allows ATM or Ethernet or PPP traffic to be transmitted across telephone lines, cable wires, optical fibers, or wireless radio frequencies. On the receiving end is another modem that re-converts the transmission format back into digital data packets. This allows network bridging using telephone, cable, optical, and radio connection methods. The modem also provides handshake protocols, so that the devices on each end of"
"requirements compared to a hardware modem, whether external or internal, to the point that most modems that are integrated in portable computer systems (including high-end laptops and PDAs) are softmodems. Because they do so little by themselves, a computer program could use a Softmodem as something other than a modem; for example, it could emulate an answering machine or a signal generator. Most PC serial ports, the traditional interface for external hardware modems, are limited to 115,200 bits per second by UART limitations, though some ports are capable of 230,400 bit/s. V.92 modems with V.44 compression can have an effective"
"therefore designed from the outset to carry higher frequencies. A single cable can carry radio and television signals at the same time as broadband internet service without interference. Newer types of broadband modems are also available, including satellite modems and power line modems. Most consumers did not know about networking and routers when broadband became available. However, many people knew that a modem connected a computer to the Internet over a telephone line. To take advantage of consumers' familiarity with modems, companies called these devices ""broadband modems"" rather than using less familiar terms such as ""adapter"", ""interface"", ""transceiver"", or ""bridge""."
"DSL) are external devices with either Ethernet connections for single PCs or routers, or built-in routers of their own; these interfaces require a full-hardware implementation. Most current broadband modems with USB jacks also have Ethernet jacks, and thus are full-hardware modems. Often, the term ""Winmodem"" or ""softmodem"" is used in a derogatory manner, as opposed to hardware or ""real"" modems. The argument is that a softmodem isn't a real modem at all, but rather a simple electrical interface between computer and phone line, limiting itself to very basic functions such as voltage/current adaptation and functioning essentially as a DAC/ADC, much"
"Cable modem A cable modem is a type of network bridge that provides bi-directional data communication via radio frequency channels on a hybrid fibre-coaxial (HFC) and radio frequency over glass (RFoG) infrastructure. Cable modems are primarily used to deliver broadband Internet access in the form of cable Internet, taking advantage of the high bandwidth of a HFC and RFoG network. They are commonly deployed in Australia, Europe, Asia and America. Internet Experiment Note (IEN) 96 (1979) describes an early RF cable modem system. From pages 2 and 3 of IEN 96: The Cable-Bus System The MITRE/Washington Cablenet system is based"
"compander functions. A modem is a contraction of ""modulator-demodulator"". The telecommunications industry referred to the device as a ""dataset"". It converts digital data from computers to analog signals for transmission over telephone lines. On the receiving end the analog signal is converted back to digital data. An audio codec converts analog audio signals into digital signals for transmission or encodes them for storage. A receiving device converts the digital signals back to analog form using an audio decoder for playback. An example of this are the codecs used in the sound cards of personal computers. A video codec accomplishes the"
"connected to a DSL modem or cable modem to connect to the internet via the ISP. The more complex kind has a built-in modem to connect to the internet without needing another device. This converged device saves desk space and simplifies wiring by replacing two electronic packages with one. It has a wired connection to the internet service provider ISP, at least one jack port for the LAN (usually four jacks) and an antenna for wireless users. The wireless gateway could support wireless 802.11b and 802.11g with speed up to 56Mbit/s, 802.11n with speed up to 300Mps and recently the"
"high-speed Internet customers may use VoIP telephony by subscribing to a third-party service, such as Vonage, MagicJack+ and NetTALK. In network topology, a cable modem is a network bridge that conforms to IEEE 802.1D for Ethernet networking (with some modifications). The cable modem bridges Ethernet frames between a customer LAN and the coax network. Technically, it is a modem because it must modulate data to transmit it over the cable network, and it must demodulate data from the cable network to receive it. With respect to the OSI model of network design, a cable modem is both Physical Layer (Layer"
"alignment need not be very precise and the modems have built in signal strength meters to help the user align the device properly. The modems have commonly used connectors such as Ethernet or Universal Serial Bus (USB). Some also have an integrated Bluetooth transceiver and double as a satellite phone. The modems also tend to have their own batteries so they can be connected to a laptop without draining its battery. The most common such system is INMARSAT's BGAN—these terminals are about the size of a briefcase and have near-symmetric connection speeds of around 350–500 kbit/s. Smaller modems exist like"
"Satellite modem A satellite modem or satmodem is a modem used to establish data transfers using a communications satellite as a relay. A satellite modem's main function is to transform an input bitstream to a radio signal and vice versa. There are some devices that include only a demodulator (and no modulator, thus only allowing data to be downloaded by satellite) that are also referred to as ""satellite modems."" These devices are used in satellite Internet access (in this case uploaded data is transferred through a conventional PSTN modem or an ADSL modem). A satellite modem is not the only"
"caused major disruption to Internet traffic for a few hours. When the Internet is accessed using a modem, digital data is converted to analog for transmission over analog networks such as the telephone and cable networks. A computer or other device accessing the Internet would either be connected directly to a modem that communicates with an Internet service provider (ISP) or the modem's Internet connection would be shared via a Local Area Network (LAN) which provides access in a limited area such as a home, school, computer laboratory, or office building. Although a connection to a LAN may provide very"
"connected to another port on the host computer. Such devices were typically expensive and generally used by larger organizations like banks, who might use one to send an end-of-day file to branch offices. Hayes was a computer hobbyist, and felt that modems would be highly compelling to users of the new 8-bit computers that would soon be known as home computers. However, existing modems were simply too expensive and difficult to use or be practical for most users. What was needed was a single modem that could do it all; connect directly to the phone, answer incoming calls, dial numbers"
"are two different types, both employing the Digital Video Broadcasting (DVB) standard as their basis: There are also industrial satellite modems intended to provide a permanent link. They are used, for example, in the Steel shankar network. Satellite modem A satellite modem or satmodem is a modem used to establish data transfers using a communications satellite as a relay. A satellite modem's main function is to transform an input bitstream to a radio signal and vice versa. There are some devices that include only a demodulator (and no modulator, thus only allowing data to be downloaded by satellite) that are"
"superseded by USB modems in the early 21st century. Some models have GPS support, providing geographical location information. Many mobile broadband modems sold nowadays also have built-in routing capabilities. They provide traditional networking interfaces such as Ethernet, USB and Wi-Fi. Models are available for both consumers and enterprises. Some require the use of an AC adapter, while others are portable and can also be powered by a USB connection or a built-in battery. An RJ11 registered jack is also present on a few of these modems, allowing the connection of a traditional home phone to make cellular calls. Numerous smartphones"
"card, which can be easily be told apart from an internal ""hardware"" modem by the significantly reduced size and component count. Softmodems can also be integrated in MiniPCI and PC cards for use in a portable computer, such as a laptop or palmtop computer, or connected via USB. Although the term has historically been used to indicate the traditional ""analog"" PSTN software modems, there are some software-based DSL modems or even routers, which work on the same principles as their PSTN ancestors, only on a larger bandwidth and on a more complex signal. One of the first software based DSL"
"support the Hayes command set and therefore can be used as a mobile broadband modem. Some mobile network operators charge a fee for this facility, if able to detect the tethering. Other networks have an allowance for full speed mobile broadband access, which—if exceeded—can result in overage charges or slower speeds. An Internet-accessing smartphone may have the same capabilities as a standalone modem, and, when connected via a USB cable to a computer, can serve as a modem for the computer. Smartphones with built-in Wi-Fi also typically provide routing and wireless access point facilities. This method of connecting is commonly"
"typically installed as a daisy chain starting from the point where the telephone company connects to the home or outlets may each be wired back to the entrance. Data wiring has two components, these are: The three most common ways data services are delivered to the home: ADSL service ADSL services are typically delivered using the telephone cabling. An ADSL modem needs a filter to segregate voice handsets from the ADSL modem. Cable Modem cable modems are typically installed in location where there is an existing Pay TV service outlet. The installation requires the installation of a Pay TV outlet"
"or with filters installed at the telephone outlets inside the customer premises. Each way has its practical and economic limitations. When the DSL modem powers up it goes through a series of steps to establish connections. The actual process varies from modem to modem but generally involves the following steps: Modern DSL gateways often integrate routing and other functionality. Their initialization is very similar to a PC boot up. The system image is loaded from the flash storage; the system boots, synchronizes the DSL connection and finally establishes the internet IP services and connection between the local network and the"
"A line that is an output on a DTE device is an input on a DCE device and vice versa so a DCE device can be connected to a DTE device with a straight wired cable. Conventionally, computers and terminals are DTE while modems and peripherals are DCE. If it is necessary to connect two DTE devices (or two DCE devices but that is more unusual) a cross-over null modem, in the form of either an adapter or a cable, must be used. Generally, serial port connectors are gendered, only allowing connectors to mate with a connector of the opposite"
"by a modem for fax and voice applications, when it is specifically placed in a fax or voice mode. Command and Data modes (modem) Command and Data modes refer to the two modes in which a computer modem may operate. These modes are defined in the Hayes command set, which is the de facto standard for all modems. These modes exist because there is only one channel of communication between the modem and the computer, which must carry both the computer's commands to the modem, as well as the data that the modem is enlisted to transmit to the remote"
"and in the end Heatherington decided the only practical one was to have the modem operate in two modes. In one, ""data mode"", all data forwarded from the computer were modulated and sent over the connected telephone line as it was with any other modem. In the other, ""command mode"", data forwarded from the computer were instead interpreted as commands. In this way, the modem could be instructed by the computer to perform various operations, such as hang up the phone or dial a number. The modem would normally start up in command mode. The problem was how to move"
"of the console's North American lifespan. There are two models of the modem adapter, 670-14140A and 670-14140B. The ""A"" model can use power from the Dreamcast game console to allow it to operate without the need of power from the telephone line. The ""B"" model does not use power from the Dreamcast thus being dependent on the power from the telephone line or a modem that runs power through the telephone line. There are multiple ways to create a server between a Dreamcast and PC using the standard modem which allows the Dreamcast to share the PC's network connection. It"
"In this case the modem is a simple interface designed to act as a digital-to-analog and an analog-to-digital converter. Softmodems are cheaper than traditional modems because they have fewer hardware components. However, the software generating and interpreting the modem tones to be sent to the softmodem uses many system resources. For online gaming, this can be a real concern. Another problem is the lack of cross-platform compatibility, meaning that non-Windows operating systems (such as Linux) often do not have an equivalent driver to operate the modem. These values are maximum values, and actual values may be slower under certain conditions"
"the connection are able to recognize each other. However, a modem generally provides few other network functions. A wireless access point can function in a similar fashion to a modem. It can allow a direct connection from a home LAN to a WAN, if a wireless router or access point is present on the WAN as well. However, many modems now incorporate the features mentioned below and thus are appropriately described as residential gateways. A residential gateway usually provides It may also provide other functions such as Dynamic DNS. Most routers are self-contained components, using internally stored firmware. They are"
"the modem automatically paces its transmission to match the audio sampling rate). The modem never stops transmitting until the computer tells it to stop, which is usually with CTRL-C. The data is always terminated with DLE+!, and all DLE bytes naturally occurring in the stream are sent twice to differentiate them from normal DLE messages. Before, during, and after recording, the modem may notify the computer host of specific events including, but not limited to, the following: When the modem wants to tell the host about these, it sends a DLE byte, plus a (usually) 1-byte message describing the event."